package com.lb.tools.lbtools.tools;

import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

/**
 * Created with IntelliJ IDEA.
 * Description:二维码生成
 * 注意生成二维码和解析过程中的编码必须为GBK，否则解析过程会出错。
 * User: liubin
 * Date: 2017-11-24
 * Time: 上午 10:13
 */
public class QRCodeUtil {
    /**
     * 二维码宽高度默认200
     */
    private static final int DEFAULT_IMAGE_WIDTH = 300;
    private static final int DEFAULT_IMAGE_HEIGHT = 300;

    /**
     * 生成带图片二维码时内部图片大小
     */
    private static final int INNER_IMAGE_WIDTH = 60;
    private static final int INNER_IMAGE_HEIGHT = 60;
    private static final int IMAGE_HALF_WIDTH = INNER_IMAGE_WIDTH / 2;
    private static final int FRAME_WIDTH = 2;

    /**
     * 生成普通二维码
     *
     * @param contents 内容
     * @param width 二维码宽度，如果小于0，则按默认大小生成
     * @param height 二维码高度，如果小于0，则按默认大小生成
     * @param imgPath 生成后的文件完整存放路径，包含文件名。形如D:\aa.jpg
     */
    public static void encodePR(String contents, int width, int height,
                                String imgPath)
    {
        Map<EncodeHintType, Object> hints = new HashMap<EncodeHintType, Object>();
        // 指定纠错等级
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);
        // 指定编码格式
        hints.put(EncodeHintType.CHARACTER_SET, "GBK");
        if (width <= 0 || height <= 0)
        {
            width = DEFAULT_IMAGE_WIDTH;
            height = DEFAULT_IMAGE_HEIGHT;
        }
        try
        {
            BitMatrix bitMatrix = new MultiFormatWriter().encode(contents,
                    BarcodeFormat.QR_CODE, width, height, hints);
            MatrixToImageWriter.writeToStream(bitMatrix, "jpg",
                    new FileOutputStream(imgPath));
        } catch (Exception e)
        {
            e.printStackTrace();
        }
    }

    /**
     * 生成带图片的二维码
     *
     * @param content
     * @param width
     * @param height
     * @param srcImagePath
     * @param destImagePath
     */
    public static void encodePR(String content, int width, int height,
                                String srcImagePath, String destImagePath)
    {
        try
        {
            ImageIO.write(genBarcode(content, width, height, srcImagePath),
                    "jpg", new File(destImagePath));
        } catch (IOException e)
        {
            e.printStackTrace();
        } catch (WriterException e)
        {
            e.printStackTrace();
        }
    }

    /**
     * 针对二维码进行解析
     *
     * @param imgPath 二维码文件路径
     * @return
     */
    public static String decodePR(String imgPath)
    {
        BufferedImage image = null;
        Result result = null;
        try
        {
            image = ImageIO.read(new File(imgPath));
            if (image == null)
            {
                throw new RuntimeException("the decode image may be not exists.");
            }
            LuminanceSource source = new BufferedImageLuminanceSource(image);
            BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));

            Map<DecodeHintType, Object> hints = new HashMap<DecodeHintType, Object>();
            hints.put(DecodeHintType.CHARACTER_SET, "GBK");

            result = new MultiFormatReader().decode(bitmap, hints);
            return result.getText();

        } catch (Exception e)
        {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 创建条形码
     *
     * @param contents
     * @param width
     * @param height
     * @param imgPath
     */
    public static void encodeBar(String contents, int width, int height,
                                 String imgPath)
    {
        // 条形码的最小宽度
        int codeWidth = 98;
        codeWidth = Math.max(codeWidth, width);
        try
        {
            BitMatrix bitMatrix = new MultiFormatWriter().encode(contents,
                    BarcodeFormat.EAN_13, codeWidth, height, null);

            MatrixToImageWriter.writeToStream(bitMatrix, "png",
                    new FileOutputStream(imgPath));

        } catch (Exception e)
        {
            e.printStackTrace();
        }
    }

    /**
     * 针对条形码进行解析
     *
     * @param imgPath
     * @return
     */
    public static String decodeBar(String imgPath)
    {
        BufferedImage image = null;
        Result result = null;
        try
        {
            image = ImageIO.read(new File(imgPath));
            if (image == null)
            {
                System.out.println("the decode image may be not exit.");
            }
            LuminanceSource source = new BufferedImageLuminanceSource(image);
            BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));

            result = new MultiFormatReader().decode(bitmap, null);
            return result.getText();
        } catch (Exception e)
        {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 把传入的原始图像按高度和宽度进行缩放，生成符合要求的图标
     *
     * @param srcImageFile
     *            源文件地址
     * @param height
     *            目标高度
     * @param width
     *            目标宽度
     * @param hasFiller
     *            比例不对时是否需要补白：true为补白; false为不补白;
     * @throws IOException
     */
    private static BufferedImage scale(String srcImageFile, int height,
                                       int width, boolean hasFiller) throws IOException
    {
        double ratio = 0.0; // 缩放比例
        File file = new File(srcImageFile);
        BufferedImage srcImage = ImageIO.read(file);
        Image destImage = srcImage.getScaledInstance(width, height,
                BufferedImage.SCALE_SMOOTH);
        // 计算比例
        if ((srcImage.getHeight() > height) || (srcImage.getWidth() > width))
        {
            if (srcImage.getHeight() > srcImage.getWidth())
            {
                ratio = (new Integer(height)).doubleValue()
                        / srcImage.getHeight();
            } else
            {
                ratio = (new Integer(width)).doubleValue()
                        / srcImage.getWidth();
            }
            AffineTransformOp op = new AffineTransformOp(
                    AffineTransform.getScaleInstance(ratio, ratio), null);
            destImage = op.filter(srcImage, null);
        }
        if (hasFiller)
        {// 补白
            BufferedImage image = new BufferedImage(width, height,
                    BufferedImage.TYPE_INT_RGB);
            Graphics2D graphic = image.createGraphics();
            graphic.setColor(Color.white);
            graphic.fillRect(0, 0, width, height);
            if (width == destImage.getWidth(null)) {
                graphic.drawImage(destImage, 0,
                        (height - destImage.getHeight(null)) / 2,
                        destImage.getWidth(null), destImage.getHeight(null),
                        Color.white, null);
            }
            else {
                graphic.drawImage(destImage,
                        (width - destImage.getWidth(null)) / 2, 0,
                        destImage.getWidth(null), destImage.getHeight(null),
                        Color.white, null);
            }
            graphic.dispose();
            destImage = image;
        }
        return (BufferedImage) destImage;
    }

    /**
     * 产生带有图片的二维码缓冲图像
     *
     * @param content
     * @param width
     * @param height
     * @param srcImagePath
     * @return
     * @throws WriterException
     * @throws IOException
     */
    private static BufferedImage genBarcode(String content, int width,
                                            int height, String srcImagePath) throws WriterException,
            IOException
    {
        // 读取源图像
        BufferedImage scaleImage = scale(srcImagePath, INNER_IMAGE_WIDTH,
                INNER_IMAGE_HEIGHT, true);
        int[][] srcPixels = new int[INNER_IMAGE_WIDTH][INNER_IMAGE_HEIGHT];
        for (int i = 0; i < scaleImage.getWidth(); i++)
        {
            for (int j = 0; j < scaleImage.getHeight(); j++)
            {
                srcPixels[i][j] = scaleImage.getRGB(i, j);
            }
        }

        Map<EncodeHintType, Object> hint = new HashMap<EncodeHintType, Object>();
        hint.put(EncodeHintType.CHARACTER_SET, "GBK");
        hint.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        // 生成二维码
        MultiFormatWriter mutiWriter = new MultiFormatWriter();
        BitMatrix matrix = mutiWriter.encode(content, BarcodeFormat.QR_CODE,
                width, height, hint);

        // 二维矩阵转为一维像素数组
        int halfW = matrix.getWidth() / 2;
        int halfH = matrix.getHeight() / 2;
        int[] pixels = new int[width * height];

        for (int y = 0; y < matrix.getHeight(); y++)
        {
            for (int x = 0; x < matrix.getWidth(); x++)
            {
                // 读取图片
                if (x > halfW - IMAGE_HALF_WIDTH
                        && x < halfW + IMAGE_HALF_WIDTH
                        && y > halfH - IMAGE_HALF_WIDTH
                        && y < halfH + IMAGE_HALF_WIDTH)
                {
                    pixels[y * width + x] = srcPixels[x - halfW
                            + IMAGE_HALF_WIDTH][y - halfH + IMAGE_HALF_WIDTH];
                }
                // 在图片四周形成边框
                else if ((x > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH
                        && x < halfW - IMAGE_HALF_WIDTH + FRAME_WIDTH
                        && y > halfH - IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH
                        + IMAGE_HALF_WIDTH + FRAME_WIDTH)
                        || (x > halfW + IMAGE_HALF_WIDTH - FRAME_WIDTH
                        && x < halfW + IMAGE_HALF_WIDTH + FRAME_WIDTH
                        && y > halfH - IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH
                        + IMAGE_HALF_WIDTH + FRAME_WIDTH)
                        || (x > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH
                        && x < halfW + IMAGE_HALF_WIDTH + FRAME_WIDTH
                        && y > halfH - IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH
                        - IMAGE_HALF_WIDTH + FRAME_WIDTH)
                        || (x > halfW - IMAGE_HALF_WIDTH - FRAME_WIDTH
                        && x < halfW + IMAGE_HALF_WIDTH + FRAME_WIDTH
                        && y > halfH + IMAGE_HALF_WIDTH - FRAME_WIDTH && y < halfH
                        + IMAGE_HALF_WIDTH + FRAME_WIDTH))
                {
                    pixels[y * width + x] = 0xfffffff;
                } else
                {
                    // 此处可以修改二维码的颜色，可以分别制定二维码和背景的颜色；
                    pixels[y * width + x] = matrix.get(x, y) ? 0xff000000
                            : 0xfffffff;
                }
            }
        }

        BufferedImage image = new BufferedImage(width, height,
                BufferedImage.TYPE_INT_RGB);
        image.getRaster().setDataElements(0, 0, width, height, pixels);

        return image;
    }

    public static void main(String[] args)
    {
        String imgPath = "d:/pr1.jpg";
        String contents = "你好,李四! welcome to zxing!"
                + "\n李四的博客[http://my.oschina.net/cloudcoder]"
                + "\nEmail[xxx@163.com]";
        // 普通二维码的生成与解析
        QRCodeUtil.encodePR(contents, 0, 10, imgPath);
        System.out.println("生成二维码成功");
        System.out.println(QRCodeUtil.decodePR(imgPath));

        // 带图片的二维的生成与解析
        imgPath = "d:/pr2.png";
        String srcPath = "d:/src.jpg";
        QRCodeUtil.encodePR(contents, 300, 300, srcPath, imgPath);
        System.out.println("生成带图片的二维码成功");
        System.out.println(QRCodeUtil.decodePR(imgPath));

        // 条形码的生成与解析
        imgPath = "d:/bar.png";
        QRCodeUtil.encodeBar("6923450657713", 105, 50, imgPath);
        System.out.println("生成条形码成功");
        System.out.println(QRCodeUtil.decodeBar(imgPath));
    }
}
